michael@0: /* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
michael@0:  * This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: package org.mozilla.gecko.home;
michael@0: 
michael@0: import org.json.JSONException;
michael@0: import org.json.JSONObject;
michael@0: 
michael@0: import org.mozilla.gecko.GeckoAppShell;
michael@0: import org.mozilla.gecko.db.BrowserContract;
michael@0: import org.mozilla.gecko.db.BrowserContract.HomeItems;
michael@0: import org.mozilla.gecko.db.DBUtils;
michael@0: import org.mozilla.gecko.db.HomeProvider;
michael@0: import org.mozilla.gecko.home.HomeConfig.PanelConfig;
michael@0: import org.mozilla.gecko.home.HomePager.OnUrlOpenListener;
michael@0: import org.mozilla.gecko.home.PanelLayout.ContextMenuRegistry;
michael@0: import org.mozilla.gecko.home.PanelLayout.DatasetHandler;
michael@0: import org.mozilla.gecko.home.PanelLayout.DatasetRequest;
michael@0: import org.mozilla.gecko.util.GeckoEventListener;
michael@0: import org.mozilla.gecko.util.ThreadUtils;
michael@0: import org.mozilla.gecko.util.UiAsyncTask;
michael@0: 
michael@0: import android.app.Activity;
michael@0: import android.content.ContentResolver;
michael@0: import android.content.Context;
michael@0: import android.content.res.Configuration;
michael@0: import android.database.Cursor;
michael@0: import android.net.Uri;
michael@0: import android.os.Bundle;
michael@0: import android.support.v4.app.LoaderManager;
michael@0: import android.support.v4.app.LoaderManager.LoaderCallbacks;
michael@0: import android.support.v4.content.Loader;
michael@0: import android.util.Log;
michael@0: import android.view.LayoutInflater;
michael@0: import android.view.View;
michael@0: import android.view.ViewGroup;
michael@0: import android.widget.FrameLayout;
michael@0: 
michael@0: /**
michael@0:  * Fragment that displays dynamic content specified by a {@code PanelConfig}.
michael@0:  * The {@code DynamicPanel} UI is built based on the given {@code LayoutType}
michael@0:  * and its associated list of {@code ViewConfig}.
michael@0:  *
michael@0:  * {@code DynamicPanel} manages all necessary Loaders to load panel datasets
michael@0:  * from their respective content providers. Each panel dataset has its own
michael@0:  * associated Loader. This is enforced by defining the Loader IDs based on
michael@0:  * their associated dataset IDs.
michael@0:  *
michael@0:  * The {@code PanelLayout} can make load and reset requests on datasets via
michael@0:  * the provided {@code DatasetHandler}. This way it doesn't need to know the
michael@0:  * details of how datasets are loaded and reset. Each time a dataset is
michael@0:  * requested, {@code DynamicPanel} restarts a Loader with the respective ID (see
michael@0:  * {@code PanelDatasetHandler}).
michael@0:  *
michael@0:  * See {@code PanelLayout} for more details on how {@code DynamicPanel}
michael@0:  * receives dataset requests and delivers them back to the {@code PanelLayout}.
michael@0:  */
michael@0: public class DynamicPanel extends HomeFragment {
michael@0:     private static final String LOGTAG = "GeckoDynamicPanel";
michael@0: 
michael@0:     // Dataset ID to be used by the loader
michael@0:     private static final String DATASET_REQUEST = "dataset_request";
michael@0: 
michael@0:     // The main view for this fragment. This contains the PanelLayout and PanelAuthLayout.
michael@0:     private FrameLayout mView;
michael@0: 
michael@0:     // The panel layout associated with this panel
michael@0:     private PanelLayout mPanelLayout;
michael@0: 
michael@0:     // The layout used to show authentication UI for this panel
michael@0:     private PanelAuthLayout mPanelAuthLayout;
michael@0: 
michael@0:     // Cache used to keep track of whether or not the user has been authenticated.
michael@0:     private PanelAuthCache mPanelAuthCache;
michael@0: 
michael@0:     // Hold a reference to the UiAsyncTask we use to check the state of the
michael@0:     // PanelAuthCache, so that we can cancel it if necessary.
michael@0:     private UiAsyncTask<Void, Void, Boolean> mAuthStateTask;
michael@0: 
michael@0:     // The configuration associated with this panel
michael@0:     private PanelConfig mPanelConfig;
michael@0: 
michael@0:     // Callbacks used for the loader
michael@0:     private PanelLoaderCallbacks mLoaderCallbacks;
michael@0: 
michael@0:     // On URL open listener
michael@0:     private OnUrlOpenListener mUrlOpenListener;
michael@0: 
michael@0:     // The current UI mode in the fragment
michael@0:     private UIMode mUIMode;
michael@0: 
michael@0:     /*
michael@0:      * Different UI modes to display depending on the authentication state.
michael@0:      *
michael@0:      * PANEL: Layout to display panel data.
michael@0:      * AUTH: Authentication UI.
michael@0:      */
michael@0:     private enum UIMode {
michael@0:         PANEL,
michael@0:         AUTH
michael@0:     }
michael@0: 
michael@0:     @Override
michael@0:     public void onAttach(Activity activity) {
michael@0:         super.onAttach(activity);
michael@0: 
michael@0:         try {
michael@0:             mUrlOpenListener = (OnUrlOpenListener) activity;
michael@0:         } catch (ClassCastException e) {
michael@0:             throw new ClassCastException(activity.toString()
michael@0:                     + " must implement HomePager.OnUrlOpenListener");
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     @Override
michael@0:     public void onDetach() {
michael@0:         super.onDetach();
michael@0: 
michael@0:         mUrlOpenListener = null;
michael@0:     }
michael@0: 
michael@0:     @Override
michael@0:     public void onCreate(Bundle savedInstanceState) {
michael@0:         super.onCreate(savedInstanceState);
michael@0: 
michael@0:         final Bundle args = getArguments();
michael@0:         if (args != null) {
michael@0:             mPanelConfig = (PanelConfig) args.getParcelable(HomePager.PANEL_CONFIG_ARG);
michael@0:         }
michael@0: 
michael@0:         if (mPanelConfig == null) {
michael@0:             throw new IllegalStateException("Can't create a DynamicPanel without a PanelConfig");
michael@0:         }
michael@0: 
michael@0:         mPanelAuthCache = new PanelAuthCache(getActivity());
michael@0:     }
michael@0: 
michael@0:     @Override
michael@0:     public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
michael@0:         mView = new FrameLayout(getActivity());
michael@0:         return mView;
michael@0:     }
michael@0: 
michael@0:     @Override
michael@0:     public void onViewCreated(View view, Bundle savedInstanceState) {
michael@0:         super.onViewCreated(view, savedInstanceState);
michael@0: 
michael@0:         // Restore whatever the UI mode the fragment had before
michael@0:         // a device rotation.
michael@0:         if (mUIMode != null) {
michael@0:             setUIMode(mUIMode);
michael@0:         }
michael@0: 
michael@0:         mPanelAuthCache.setOnChangeListener(new PanelAuthChangeListener());
michael@0:     }
michael@0: 
michael@0:     @Override
michael@0:     public void onDestroyView() {
michael@0:         super.onDestroyView();
michael@0:         mView = null;
michael@0:         mPanelLayout = null;
michael@0:         mPanelAuthLayout = null;
michael@0: 
michael@0:         mPanelAuthCache.setOnChangeListener(null);
michael@0: 
michael@0:         if (mAuthStateTask != null) {
michael@0:             mAuthStateTask.cancel(true);
michael@0:             mAuthStateTask = null;
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     @Override
michael@0:     public void onConfigurationChanged(Configuration newConfig) {
michael@0:         super.onConfigurationChanged(newConfig);
michael@0: 
michael@0:         // Detach and reattach the fragment as the layout changes.
michael@0:         if (isVisible()) {
michael@0:             getFragmentManager().beginTransaction()
michael@0:                                 .detach(this)
michael@0:                                 .attach(this)
michael@0:                                 .commitAllowingStateLoss();
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     @Override
michael@0:     public void onActivityCreated(Bundle savedInstanceState) {
michael@0:         super.onActivityCreated(savedInstanceState);
michael@0: 
michael@0:         // Create callbacks before the initial loader is started.
michael@0:         mLoaderCallbacks = new PanelLoaderCallbacks();
michael@0:         loadIfVisible();
michael@0:     }
michael@0: 
michael@0:     @Override
michael@0:     protected void load() {
michael@0:         Log.d(LOGTAG, "Loading layout");
michael@0: 
michael@0:         if (requiresAuth()) {
michael@0:             mAuthStateTask = new UiAsyncTask<Void, Void, Boolean>(ThreadUtils.getBackgroundHandler()) {
michael@0:                 @Override
michael@0:                 public synchronized Boolean doInBackground(Void... params) {
michael@0:                     return mPanelAuthCache.isAuthenticated(mPanelConfig.getId());
michael@0:                 }
michael@0: 
michael@0:                 @Override
michael@0:                 public void onPostExecute(Boolean isAuthenticated) {
michael@0:                     mAuthStateTask = null;
michael@0:                     setUIMode(isAuthenticated ? UIMode.PANEL : UIMode.AUTH);
michael@0:                 }
michael@0:             };
michael@0:             mAuthStateTask.execute();
michael@0:         } else {
michael@0:             setUIMode(UIMode.PANEL);
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * @return true if this panel requires authentication.
michael@0:      */
michael@0:     private boolean requiresAuth() {
michael@0:         return mPanelConfig.getAuthConfig() != null;
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Lazily creates layout for panel data.
michael@0:      */
michael@0:     private void createPanelLayout() {
michael@0:         final ContextMenuRegistry contextMenuRegistry = new ContextMenuRegistry() {
michael@0:             @Override
michael@0:             public void register(View view) {
michael@0:                 registerForContextMenu(view);
michael@0:             }
michael@0:         };
michael@0: 
michael@0:         switch(mPanelConfig.getLayoutType()) {
michael@0:             case FRAME:
michael@0:                 final PanelDatasetHandler datasetHandler = new PanelDatasetHandler();
michael@0:                 mPanelLayout = new FramePanelLayout(getActivity(), mPanelConfig, datasetHandler,
michael@0:                         mUrlOpenListener, contextMenuRegistry);
michael@0:                 break;
michael@0: 
michael@0:             default:
michael@0:                 throw new IllegalStateException("Unrecognized layout type in DynamicPanel");
michael@0:         }
michael@0: 
michael@0:         Log.d(LOGTAG, "Created layout of type: " + mPanelConfig.getLayoutType());
michael@0:         mView.addView(mPanelLayout);
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Lazily creates layout for authentication UI.
michael@0:      */
michael@0:     private void createPanelAuthLayout() {
michael@0:         mPanelAuthLayout = new PanelAuthLayout(getActivity(), mPanelConfig);
michael@0:         mView.addView(mPanelAuthLayout, 0);
michael@0:     }
michael@0: 
michael@0:     private void setUIMode(UIMode mode) {
michael@0:         switch(mode) {
michael@0:             case PANEL:
michael@0:                 if (mPanelAuthLayout != null) {
michael@0:                     mPanelAuthLayout.setVisibility(View.GONE);
michael@0:                 }
michael@0:                 if (mPanelLayout == null) {
michael@0:                     createPanelLayout();
michael@0:                 }
michael@0:                 mPanelLayout.setVisibility(View.VISIBLE);
michael@0: 
michael@0:                 // Only trigger a reload if the UI mode has changed
michael@0:                 // (e.g. auth cache changes) and the fragment is allowed
michael@0:                 // to load its contents. Any loaders associated with the
michael@0:                 // panel layout will be automatically re-bound after a
michael@0:                 // device rotation, no need to explicitly load it again.
michael@0:                 if (mUIMode != mode && canLoad()) {
michael@0:                     mPanelLayout.load();
michael@0:                 }
michael@0:                 break;
michael@0: 
michael@0:             case AUTH:
michael@0:                 if (mPanelLayout != null) {
michael@0:                     mPanelLayout.setVisibility(View.GONE);
michael@0:                 }
michael@0:                 if (mPanelAuthLayout == null) {
michael@0:                     createPanelAuthLayout();
michael@0:                 }
michael@0:                 mPanelAuthLayout.setVisibility(View.VISIBLE);
michael@0:                 break;
michael@0: 
michael@0:             default:
michael@0:                 throw new IllegalStateException("Unrecognized UIMode in DynamicPanel");
michael@0:         }
michael@0: 
michael@0:         mUIMode = mode;
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Used by the PanelLayout to make load and reset requests to
michael@0:      * the holding fragment.
michael@0:      */
michael@0:     private class PanelDatasetHandler implements DatasetHandler {
michael@0:         @Override
michael@0:         public void requestDataset(DatasetRequest request) {
michael@0:             Log.d(LOGTAG, "Requesting request: " + request);
michael@0: 
michael@0:             // Ignore dataset requests while the fragment is not
michael@0:             // allowed to load its content.
michael@0:             if (!getCanLoadHint()) {
michael@0:                 return;
michael@0:             }
michael@0: 
michael@0:             final Bundle bundle = new Bundle();
michael@0:             bundle.putParcelable(DATASET_REQUEST, request);
michael@0: 
michael@0:             getLoaderManager().restartLoader(request.getViewIndex(),
michael@0:                                              bundle, mLoaderCallbacks);
michael@0:         }
michael@0: 
michael@0:         @Override
michael@0:         public void resetDataset(int viewIndex) {
michael@0:             Log.d(LOGTAG, "Resetting dataset: " + viewIndex);
michael@0: 
michael@0:             final LoaderManager lm = getLoaderManager();
michael@0: 
michael@0:             // Release any resources associated with the dataset if
michael@0:             // it's currently loaded in memory.
michael@0:             final Loader<?> datasetLoader = lm.getLoader(viewIndex);
michael@0:             if (datasetLoader != null) {
michael@0:                 datasetLoader.reset();
michael@0:             }
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Cursor loader for the panel datasets.
michael@0:      */
michael@0:     private static class PanelDatasetLoader extends SimpleCursorLoader {
michael@0:         private DatasetRequest mRequest;
michael@0: 
michael@0:         public PanelDatasetLoader(Context context, DatasetRequest request) {
michael@0:             super(context);
michael@0:             mRequest = request;
michael@0:         }
michael@0: 
michael@0:         public DatasetRequest getRequest() {
michael@0:             return mRequest;
michael@0:         }
michael@0: 
michael@0:         @Override
michael@0:         public void onContentChanged() {
michael@0:             // Ensure the refresh request doesn't affect the view's filter
michael@0:             // stack (i.e. use DATASET_LOAD type) but keep the current
michael@0:             // dataset ID and filter.
michael@0:             final DatasetRequest newRequest =
michael@0:                    new DatasetRequest(mRequest.getViewIndex(),
michael@0:                                       DatasetRequest.Type.DATASET_LOAD,
michael@0:                                       mRequest.getDatasetId(),
michael@0:                                       mRequest.getFilterDetail());
michael@0: 
michael@0:             mRequest = newRequest;
michael@0:             super.onContentChanged();
michael@0:         }
michael@0: 
michael@0:         @Override
michael@0:         public Cursor loadCursor() {
michael@0:             final ContentResolver cr = getContext().getContentResolver();
michael@0: 
michael@0:             final String selection;
michael@0:             final String[] selectionArgs;
michael@0: 
michael@0:             // Null represents the root filter
michael@0:             if (mRequest.getFilter() == null) {
michael@0:                 selection = HomeItems.FILTER + " IS NULL";
michael@0:                 selectionArgs = null;
michael@0:             } else {
michael@0:                 selection = HomeItems.FILTER + " = ?";
michael@0:                 selectionArgs = new String[] { mRequest.getFilter() };
michael@0:             }
michael@0: 
michael@0:             final Uri queryUri = HomeItems.CONTENT_URI.buildUpon()
michael@0:                                                       .appendQueryParameter(BrowserContract.PARAM_DATASET_ID,
michael@0:                                                                             mRequest.getDatasetId())
michael@0:                                                       .build();
michael@0: 
michael@0:             // XXX: You can use HomeItems.CONTENT_FAKE_URI for development
michael@0:             // to pull items from fake_home_items.json.
michael@0:             return cr.query(queryUri, null, selection, selectionArgs, null);
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * LoaderCallbacks implementation that interacts with the LoaderManager.
michael@0:      */
michael@0:     private class PanelLoaderCallbacks implements LoaderCallbacks<Cursor> {
michael@0:         @Override
michael@0:         public Loader<Cursor> onCreateLoader(int id, Bundle args) {
michael@0:             final DatasetRequest request = (DatasetRequest) args.getParcelable(DATASET_REQUEST);
michael@0: 
michael@0:             Log.d(LOGTAG, "Creating loader for request: " + request);
michael@0:             return new PanelDatasetLoader(getActivity(), request);
michael@0:         }
michael@0: 
michael@0:         @Override
michael@0:         public void onLoadFinished(Loader<Cursor> loader, Cursor cursor) {
michael@0:             final DatasetRequest request = getRequestFromLoader(loader);
michael@0:             Log.d(LOGTAG, "Finished loader for request: " + request);
michael@0: 
michael@0:             if (mPanelLayout != null) {
michael@0:                 mPanelLayout.deliverDataset(request, cursor);
michael@0:             }
michael@0:         }
michael@0: 
michael@0:         @Override
michael@0:         public void onLoaderReset(Loader<Cursor> loader) {
michael@0:             final DatasetRequest request = getRequestFromLoader(loader);
michael@0:             Log.d(LOGTAG, "Resetting loader for request: " + request);
michael@0: 
michael@0:             if (mPanelLayout != null) {
michael@0:                 mPanelLayout.releaseDataset(request.getViewIndex());
michael@0:             }
michael@0:         }
michael@0: 
michael@0:         private DatasetRequest getRequestFromLoader(Loader<Cursor> loader) {
michael@0:             final PanelDatasetLoader datasetLoader = (PanelDatasetLoader) loader;
michael@0:             return datasetLoader.getRequest();
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     private class PanelAuthChangeListener implements PanelAuthCache.OnChangeListener {
michael@0:         @Override
michael@0:         public void onChange(String panelId, boolean isAuthenticated) {
michael@0:             if (!mPanelConfig.getId().equals(panelId)) {
michael@0:                 return;
michael@0:             }
michael@0: 
michael@0:             setUIMode(isAuthenticated ? UIMode.PANEL : UIMode.AUTH);
michael@0:         }
michael@0:     }
michael@0: }